1. Field of the Invention
The present invention generally relates to a light source unit and a projector apparatus equipped with the light source unit, and more particularly to a light source unit miniaturized without decreasing the utilization efficiency of light from a light source and a projector apparatus equipped with the light source unit.
2. Description of the Related Art
A projector apparatus is configured to display an image on a screen by making the light that has outgone from a light source unit be incident into a mirror tunnel to make the light having a uniform intensity distribution after making the light pass through a color wheel, and by projecting the light with the light quantity being switched at each pixel with a micro-mirror device, a liquid crystal display device or the like.
As shown in FIG. 9, a light source unit 50 is composed of a light source 51 radiating light, a convex lens 52, which is disposed on an optical axis K for condensing the light emitted form the light source 51, and a mirror tunnel 53, into which the light that has outgone from the convex lens 52 is made to be incident (see JP Hei 06-51401A).
The light source 51 is composed of a reflector 54 and a lamp 55 inserted into the reflector 54. The lamp 55 is composed of a bulb 56 and electrode introducing units 59, and the lamp 55 is inserted so that the bulb 56 may be located in the reflector 54. In addition, the color wheel is omitted in FIG. 9.
Here, a part of the light that has been emitted from the bulb 56 and has been reflected by the inner wall of the reflector 54 strikes the electrode introducing unit 59, and the light quantity of the light is attenuated. Moreover, the convex lens 52 cannot sufficiently radiate the light reflected by the reflector 54 onto the incidence plane 53a of the mirror tunnel 53.
Accordingly, in order to secure a certain light quantity, it becomes necessary for the light source unit 50 to have a size equal to a certain size or more, and a projector apparatus having the light source unit 50 built therein has a tendency to become large in size. Consequently, the projector apparatus is not always easy to carry and to install.
Although the size of a light source unit is more preferable to be smaller from the viewpoint of miniaturizing the whole body, it has been necessary for the size of the lamp of the light source unit to be a certain size or more from the viewpoint of securing a light quantity.